Factual error: When Ney comes to make his report to Napoleon after Quatre-bras(Where Ney engaged the Allied army), he throws a captured British flag down before Napoleon. This flag is a green Regimental flag, with a sphinx insignia - But the only British flag captured at Quatre-bras was the Kings Colors of the 69th, which would be a great Union Flag with '69' in gold leaves.
Factual error: In the opening text, the movie states that England was one of the countries that defeated Napoleon at Leipzig. However, England did not participate in that battle; Wellington had just defeated Soult and launched an invasion of southern France at the time. Interestingly, Sweden did send about 30,000 soldiers to fight at Leipzig, but is not mentioned.